Landfill gas generation after mechanical biological treatment of municipal solid waste. Estimation of gas generation rate constants.
Mechanical biological treatment (MBT) of residual municipal solid waste (RMSW) was investigated with respect to landfill gas generation. Mechanically treated RMSW was sampled at a full-scale plant and aerobically stabilized for 8 and 15 weeks. Anaerobic tests were performed on the aerobically treated waste (MBTW) in order to estimate the gas generation rate constants (k,y(-1)), the potential gas generation capacity (L(o), Nl/kg) and the amount of gasifiable organic carbon. Experimental results show how MBT allowed for a reduction of the non-methanogenic phase and of the landfill gas generation potential by, respectively, 67% and 83% (8 weeks treatment), 82% and 91% (15 weeks treatment), compared to the raw waste. The amount of gasified organic carbon after 8 weeks and 15 weeks of treatment was equal to 11.01+/-1.25kgC/t(MBTW) and 4.54+/-0.87kgC/t(MBTW), respectively, that is 81% and 93% less than the amount gasified from the raw waste. The values of gas generation rate constants obtained for MBTW anaerobic degradation (0.0347-0.0803y(-1)) resemble those usually reported for the slowly and moderately degradable fractions of raw MSW. Simulations performed using a prediction model support the hypothesis that due to the low production rate, gas production from MBTW landfills is well-suited to a passive management strategy.
Gioannis
G De
GD
Department of Geoengineering and Environmental Technologies, University of Cagliari, Piazza D'Armi, 09123 Cagliari, Italy.
Muntoni
A
A
Cappai
G
G
Milia
S
S
D000393:Air Pollutants / Q000032:analysis* / Q000378:metabolism; D000693:Anaerobiosis; D001673:Biodegradation, Environmental; D002244:Carbon / Q000032:analysis / Q000378:metabolism; D002947:Cities; D004784:Environmental Monitoring; D005740:Gases / Q000032:analysis* / Q000378:metabolism; D008697:Methane / Q000032:analysis / Q000378:metabolism; D009930:Organic Chemicals / Q000032:analysis / Q000378:metabolism; D012037:Refuse Disposal; D013997:Time Factors
D000393:Air Pollutants; D005740:Gases; D009930:Organic Chemicals; D002244:Carbon; D008697:Methane